1. Field of the Invention
The present invention relates to a printing apparatus, a printing system, a print control method, and a storage medium, and, more particularly, to a printing apparatus, a printing system, a print control method, and a storage medium ideally suited for performing printing that employs, as communication means, a predetermined interface such as an IEEE 1394 interface, which is a serial interface standard established by the Institute of Electrical and Electronic Engineers.
2. Description of the Related Art
Hitherto, a printing apparatus or a printer is adapted to pull out paper from a paper holding device, feed the paper to an image forming device to perform printing, and eject the paper. FIGS. 35A through 35H are schematic diagrams illustrating a series of printing steps in the printer. FIG. 35A illustrates a state wherein a first sheet of paper is being pulled out, FIG. 35B illustrates a state wherein the first sheet of paper is being fed to the image forming device, FIG. 35C illustrates another state wherein the first sheet of paper is being fed to the image forming device, FIG. 35D illustrates a state wherein the first sheet of paper for which printing has been finished is being ejected, FIG. 35E illustrates a state wherein a second sheet of paper is being printed, FIG. 35F illustrates a state wherein a third sheet of paper is being pulled out, FIG. 35G illustrates a state wherein the third sheet of paper is being printed, and FIG. 35H illustrates a state wherein a fourth sheet of paper is being pulled out.
In short, the first sheet of paper is picked up as shown in FIG. 35A and printed by undergoing the steps illustrated by FIGS. 35B, 35C, and 35D in this order. Before the first paper is ejected as shown in FIG. 35D, the second sheet of paper is picked up and printed as shown in FIG. 35E. This operation is necessary to improve the printing throughput of the printer. It can be understood that at least two sheets of paper are simultaneously present in the printer in this example.
In a conventional printing system formed of a printing apparatus or a printer and a host apparatus or a host computer, recovery from a jam that has taken place in the printing apparatus is performed according to either of the following procedures:
(A) A receiving buffer memory in the printer is provided with a capacity that is sufficient for storing text data for at least two pages. If a jam occurs, recovery from the jam is accomplished by reprinting the text data of a pertinent page that has been stored in the printer.
(B) If a jam occurs, the jam is reported to a host computer to have it retransmit the text data of the page where the jam has taken place.
However, the method of (A) presents a shortcoming of requiring a larger capacity of a receiving buffer memory of the printer, leading to higher cost. In particular, the printer will be larger, and an increase in cost would be critical in a printing system wherein its printer holds four or five sheets of paper when printing. The method of (B) has been disadvantageous in that burden on the host computer will be heavier since the host computer retransmits the text data of the page where the jam has occurred. This is especially disadvantageous because no standard system is presently available for sending text data of a jammed page from a host computer to a printer, and hence, there is no choice but to retransmit the whole text data, which is also extremely inconvenient for a user.
Accordingly, the present invention has been made with a view toward overcoming the shortcomings described above, and it is an object thereof to provide a printing apparatus, a printing system, a print control method, and a storage medium that features high efficiency, an extremely small capacity of a receiving buffer memory of the printing apparatus, and an extremely small burden on a host apparatus.
To this end, according to one aspect of the present invention, there is provided a printing apparatus that is capable of communicating with a host apparatus and includes control means for reading print data stored in the host apparatus on the basis of address information regarding the print data notified from the host apparatus in order to perform printing.
In a preferred form of the present invention, the printing apparatus includes communicating means for communicating with a host apparatus, and printing means for printing on a recording medium, wherein the control means reads print data stored in the host apparatus on the basis of an address of an information block that includes address information regarding the print data notified from the host apparatus via the communicating means, and causes the printing means to perform printing.
In another preferred form of the present invention, the control means sends a report indicating that the printing of the print data has been completed and also information regarding a page on which printing has been completed back to the host apparatus as a status via the communicating means, and the host apparatus clears print data regarding the page on which printing has been completed upon receipt of the printing complete status via the communicating means, and loads at the cleared position print data regarding a next page to be printed if there is a next page to be printed.
In a further preferred form of the present invention, upon receipt of the printing complete status via the communicating means, the host apparatus retains print data other than the print data regarding the page on which printing has been completed.
In another preferred from of the present invention, the communicating means performs communication that conforms to an IEEE 1394 interface standard.
According to another aspect of the present invention, there is provided a printing system including a printing apparatus and a host apparatus that are able to communicate with each other, wherein the host apparatus has storing means that can be accessed by the printing apparatus and stores print data, and host control means for notifying the printing apparatus of address information of print data, wherein the printing apparatus includes print control means for reading print data stored in the storing means of the host apparatus on the basis of address information of the print data notified from the host apparatus, and causes printing to be performed.
In a preferred form of the present invention, the host apparatus includes host communicating means for communicating with a printing apparatus, and the printing apparatus includes print communicating means for communicating with the host apparatus and printing means for printing on a recording medium, wherein the print control means reads print data stored in the storing means of the host apparatus on the basis of an address of an information block that includes address information regarding the print data notified from the host apparatus via the print communicating means, and causes the printing means to perform printing.
In another preferred form of the present invention, the print control means sends a report indicating that the printing of the print data has been completed and also information regarding a page on which printing has been completed back, as a status, to the host apparatus via the print communicating means, and the host control means clears print data regarding the page on which printing has been completed from the storing means upon receipt of a printing complete status via the host communicating means, and loads, at the cleared position in the storing means print, data regarding a next page to be printed if there is a next page to be printed.
In a further preferred form of the present invention, upon receipt of the printing complete status via the host communicating means, the host control means retains, in the storing means, print data other than the print data regarding the page on which printing has been completed.
In another preferred form of the present invention, the host communicating means and the print communicating means perform communication that conforms to an IEEE 1394 interface standard.
In a further preferred form of the present invention, an image input device such as a scanner, an image sensing device such as a digital camera, a storing device such as a hard disk, and so on other than the printing apparatus may be connected to the host apparatus via the IEEE 1394 interface.
According to yet another aspect of the present invention, there is provided a print control method applied to a printing system that includes a printing apparatus and a host apparatus that are able to communicate with each other, wherein the host apparatus performs a storing step for storing print data in storing means that can be accessed by the printing apparatus, and a host control step for notifying the printing apparatus of address information of print data, and the printing apparatus performs a print control step for reading print data stored in the storing means of the host apparatus on the basis of address information of the print data notified from the host apparatus, and for causing printing to be performed.
In a preferred form of the present invention, the host apparatus performs a host communication step for communicating with a printing apparatus, and the printing apparatus performs a print communication step for communicating with the host apparatus and a printing step for printing on a recording medium, wherein, in the print control step, print data stored in the storing means of the host apparatus is read on the basis of an address of an information block that includes address information regarding the print data notified from the host apparatus via the print communication step, and the printing is performed in the printing step.
In another preferred form of the present invention, in the print control step, a report indicating that the printing of the print data has been completed and also information regarding a page on which printing has been completed are sent back to the host apparatus as a status via the print communication step, and in the host control step, print data regarding the page on which printing has been completed is cleared from the storing means upon receipt of a printing complete status via the host communication step, and print data regarding a next page to be printed is loaded at the cleared position in the storing means if there is a next page to be printed.
In a further preferred form of the present invention, print data other than the print data regarding the page on which printing has been completed is retained in the storing means in the host control step upon receipt of the printing complete status via the host communicating step.
In another preferred form of the present invention, communication that conforms to an IEEE 1394 interface standard is performed in the host communication step and the print communication step.
In a further preferred form of the present invention, the print control method is applicable to a printing system wherein an image input device such as a scanner, an image sensing device such as a digital camera, a storing device such as a hard disk, and so on other than the printing apparatus can be connected to the host apparatus via the IEEE 1394 interface.
According to a further aspect of the present invention, there is provided a storage medium that stores a program for implementing a print control method applied to a printing system that includes a printing apparatus and a host apparatus that are able to communicate with each other and that can be accessed by a computer, wherein the print control method includes a storing step for storing print data in storing means that can be accessed by the printing apparatus, a host control step for notifying the printing apparatus of address information of the print data, and a print control step for reading the print data stored in the storing means of the host apparatus on the basis of the address information of the print data notified from the host apparatus and for carrying out printing.